oggvorbis

Úvod

The OGG/Vorbis file format, as defined by » https://www.vorbis.com/, is a scheme for compressing audio streams by multiple factors with a minimum of quality loss. This extension adds Ogg Vorbis support to PHP's URL Wrappers. When used in read mode, compressed OGG/Vorbis data is expanded to raw PCM audio in one of six PCM encoding formats listed below.

Požiadavky

This extension requires PHP >= 4.3.0, » libogg >= 1.0, and » libvorbis >= 1.0.

Runtime Konfigurácia

Toto rozšírenie nemá žiadne konfiguračné direktívy definované v php.ini.

Inštalácia

Dodatočné informácie ako sú nové vydania, downloady, zdrojové súbory, informácie od spracovávateľa, a CHANGELOG, je možné nájsť tu: » https://pecl.php.net/package/oggvorbis

Context options

**OGG/Vorbis tuning options**
Option	Definition	Relevance	Default
pcm_mode	PCM byte encoding used. See constants below.	Read / Write	`OGGVORBIS_PCM_S16_LE`
rate	PCM Sampling rate. Measured in Hz.	Write only	`44100`
bitrate	Vorbis Average Bitrate Encoding / Variable Bitrate Encoding. Measured in bps (ABR) or Quality level (VBR: 0.0 to 1.0). 128000 ABR is rough equal to 0.4 VBR.	Write only	`128000`
channels	Number of PCM channels. 1 == Mono, 2 == Stereo.	Write only	`2`
serialno	Serial Number of stream within file. Must be unique within file. Because of the potential to select a duplicate serial number within a chained file, make efforts to manually assign unique numbers when encoding.	Write only	Random
comments	Associative array of file comments. Will be translated to strtoupper($name) . "=$value". Note: This context option is not available in oggvorbis-0.1	Write only	`array('ENCODER' => 'PHP/OggVorbis, https://pear.php.net/oggvorbis')`

Preddefinované Konštanty

Konštanty uvedené nižšie sú definované týmto rozšírením a budú dostupné iba keď rozšírenie bolo buď kompilované do PHP alebo dynamicky načítané za behu (runtime).

**OGG/Vorbis supports PCM encodings in the following formats**
Constant	Definition
`OGGVORBIS_PCM_U8`	Unsigned 8-bit PCM.
`OGGVORBIS_PCM_S8`	Signed 8-bit PCM.
`OGGVORBIS_PCM_U16_LE`	Unsigned 16-bit PCM. Little Endian byte order.
`OGGVORBIS_PCM_U16_BE`	Unsigned 16-bit PCM. Big Endian byte order.
`OGGVORBIS_PCM_S16_LE`	Signed 16-bit PCM. Little Endian byte order.
`OGGVORBIS_PCM_S16_BE`	Signed 16-bit PCM. Big Endian byte order.